Is it possible to set a max time limit to complete an entire quiz or is it just timed per question? Also can total duration be shown and stored in the test results?
Yes, you can, but will need some advanced actions using system variables lie cpInfoEpochMS, cpInoElapsedTimeMS.....
Sorry, but I have another blog post, older one, which was created when SWF output was the rule.
You also have a Timer and an Hourglass interaction which could be useful as well.
Lot is possible with Captivate, didn't even talk about JS yet. However, first try to understand the basics of Quizzes. In the eLearning Community I have a sequence of 5 blog posts doing so. Recently the firth was published (it is on the home page). Soon I will start with 'tweaking tips.